Oil storage



J. K. JORDAN Oct. 10, 1961 OIL STORAGE Filed June 6, 1958 INFLATABLE FIG5 INVENTOR.

JAMES K. JORDAN,

ATTORNEY.

SALT DONE United States Patent 3,003,322 OIL STORAGE James K. Jordan,Houston, Tex., assignor, by mesne assignments, to Jersey ProductionResearch Company, Tulsa, Okla., a corporation of Delaware Filed June 6,1958, Ser. No. 740,459 1 Claim. (Cl. 61-.5)

This invention concerns method and apparatus for delivery of fluids.More particularly, the invention concerns method and apparatus for thestorage of oil in subterranean cavities located offshore and delivery ofthe oil therefrom.

The development of large oil reserves ofishore has introduced manyproblems relative to the transportation and storage of produced oil. Inone known practice the oil is produced and then moved by pipe line orbarge to a shore terminal. From the terminal the oil is sent to acentral tanker loading terminal or refinery. This practice isdisadvantageous because movement of oil by barge is expensive andsubject to weather conditions; costly oflshore tank batteryinstallations are required for the dis position of separator gas; andlaying oflshore pipe lines from the tank battery installations to shoreinstallations is expensive and prohibitively so for installations inproducing areas far from shore.

On the other hand, the ability to handle offshore oil at or near theproduction area provides many advantages. For example, barge loadingfacilitiese both on shore and oflishore are eliminated or the necessityfor laying offshore pipe lines to shore terminals is eliminated; shoreterminals and large storage and tanker loading facilities at deep waterports are eliminated; and the time required for tankers to enter, loadand leave the deep water ports is reduced.

One method for handling oil production ofishore at or near the area ofproduction is the construction of an oil?- shore underground storage inconjunction with a tanker loading terminal. Thus, for example, anunderground salt cavity of suflicient size to hold many days oilproduction may be leached out and facilities may be installed forhandling this oil at a tanker loading terminal near the salt cavity.

One desirable method for bringing the oil stored in the salt cavity tothe surface at high flow rates is by displacement with the readilyavailable sea water. However, since the sea water used is relativelyfresh with respect to a saturated brine solution, each time the freshsea water is used to displace the oil in the salt cavern, an additionalportion of the salt cavity is leached out. This operation would ruin thesalt cavity eventually.

Therefore, an object of this invention is to provide a method and systemfor storing oil in underground cavities and in displacing the stored oilwith water whereby a continuous leaching process is avoided.

In a broader aspect an object of the invention is to provide improvedmethod and apparatus for displacing a fluid contained in a receptacle byanother fluid wherein the latter displacing fluid is maintained separatefrom the fluid being displaced.

Briefly, the method of the invention provides for removing fluids from asubterranean cavity which comprises injecting a first fluid into thecavity to force a second fluid contained in the cavity to the surfacewhile maintaining the first fluid separate from the wall of the cavityand separate from the second fluid.

The system of the invention for removing fluids from a subterraneancavity comprises at least a first conduit extending from the surfaceinto the cavity, at least a second conduit extending from the surfaceinto the cavity,

and an inflatable bag arranged in the cavity, the neck thereof beingarranged in the second conduit.

The above objects and other objects of the invention will be apparentfrom a more detailed description of the invention taken in conjunctionwith the drawing wherein:

FIG. 1 is a vertical view through a section of the subsurface showingthe bag in deflated position;

FIG. 2 is a vertical view through a section of the subsurface andshowing the bag partially inflated;

FIG. 3 is a vertical view through a section of thesubsurface and showingthe bag substantially completely inflated;

FIG. 4 is a vertical view of the inflatable bag in lowering-in position;and

FIG. 5 is an enlarged vertical view of the coupling connecting theinflatable bag to the cable landed in the pipe.

FIGS. 1 through 3 show a cavity 15 formed in a salt dome 10 located inthe ground 11 underlying a body of water 12. Concentric pipes 13 and 14are arranged to extend from above the surface of the water to the upperpart of cavity 15 and a pipe 16 is arranged to extend from above thesurface of the water into cavity 15, as shown. An inflatable bag 17 isarranged in cavity 15 and is connected to a cable 18 which extendsthrough the upper end of pipe 16. A conduit 19 is connected to pipe 16and a conduit 20 is connected to pipe 13 and fluidly communicates withthe annulus between pipes 13 and 14.

Valves 7, 8, and 9 are provided on conduits 14, 19, and 20,respectively, to control the flow of fluid through these pipes. Acoupling provided with a stuifing box 21 which seals off around cable 18is connected to the upper end of pipe 16.

FIG. 4 is a detailed view of the bag in deflated lowering-in positionarranged in pipe 16.

Bag 17 is compressed as by wrapping, as shown. Split rings 22 retain thebag in wrapped position until the bag begins to inflate. Other devicessuch as frangible rings, releasable sheaths, etc. may be used in placeof the split rings. The neck of the bag is connected to a coupling 23which is a hollow member secured to cable 18 and provided with openings24 Which openings fluidly communicate with the interior of bag 17. Thelower end of bag 17 has attached thereteo a cup packer 25 which may beused to aid in moving bag 17 downwardly through pipe 16.

In FIG. 5 is illustrated coupling 23 and landing apparatus whichrestrains or prevents the coupling from moving out of the lower end ofpipe 16. The landing apparatus includes a shoulder portion 26 formed oncoupling 23 which is adapted to engage with or land on a shoulder 27formed on the lower end of tubing 16.

Cavity 15 is formed by drilling a hole into salt dome 10 and settingpipe 13 therein. Pipe 14 is arranged to extend through pipe 13 and aportion of the salt dome is leached out by circulating water down onepipe and up the other pipe. After the cavity has been formedsufiiciently large a second hole is drilled to cavity 15 and pipe 16 isset in this hole. Then bag 17 is lowered through pipe 16 on cable 18until shoulder 26 of coupling 23 is landed on shoulder 27 of pipe 16.

Cavity 15 is filled with oil by pumping oil through pipe 14. The waterused in leaching will be displaced by the oil to the surface through theannulus between pipes 13 and 14. When it is desired to remove the oilfrom the storage cavity sea Water is pumped through pipes 19 and 16,through openings 24 and into the interior of bag 17. As bag 17 begins toinflate, retaining rings 22 release and permit continued inflation ofthe bag. Inflating of bag 17 displaces the stored oil through theannulus between pipes 13 and 14 or through pipe 14.

When it is desired to again store oil in cavity 15, oil is pumpeddownwardly through pipe 14 or through the the bag. The saltwateris-displaced through coupling 23 and pipe 16'to the surface. When it isdesired to re-' move the deflated bag, it is pulled through pipe 16 bymeans of cable 18.

The operation of valves 7, 8,, and 9 is considered apparent consequentlythe manipulation of these valves during the storage-displacement cyclewas not described. St-ufiing-box 21 is used to seal oft the annulusabout cable 18 after the bag has been arranged in the cavity and baginflating fluid is about to be pumpedthrough pipes 19 and 165'A'lthoughionly onebag was illustrated in the description-of=theinvention for sufiiciently large cavities more than onebag may beusedand in accordance therewith an aocesshole'having a pipe 16 set thereinwould be employed for each bag.

The bag, is preferablyformed of a material vnot affected by hydrocarbonssuch as synthetic or neoprenerubber or a plastic material such aspolyethylene. It is of' sufiicient thickness and ductility to preventdamage to it by contact with the rough wall of the cavity and by thecontinuous folding and unfolding required by the continual storing anddisplacement of the oil.

Aithough the 'mvention has been described with regard to displacement ofoil by salt water, the scope of the invention is not to be consideredlimited to such use. The scope of'the invention encompasses displacementof any fluid by any other fluid. As an example, a gas such asair ornatural gas may be used as the bag inflating mediumnto displace water.

Having fully described the method, apparatus and objects of'theinvention, 1 claim:

A system for the storage of oil in a subterranean location underlying abody of sea water and 'for removal of oil stored in this locationcomprising an offshore subterranean salt dome provided with a cavity; atleast a first conduit extending from above the surface of the water intothe upper portion of said cavity; at least a second conduit extendingfrom above the surface of the Water into said cavity and provided with ashoulder adjacent the lower end thereof; an inflatable, deflatable bagarranged in said cavity, the neck portion of said bag being providedwith a coupling-having a shoulder en- 'gageable with said second conduitshoulder, said shoulders cooperating to prevent further downwardmovement throughsaid second conduit of the neck portion of said bag; a--cable connected to said coupling adapted to lower said bagdeflatedthrough said second conduit into said cavity; said first conduitbeing a conductor of'oil'from said cavity and saidsecond conduit being aconductor of sea water-into said bag when it is desired to displace oilstored in said cavity from said cavity-by supplying said bag-with seawater'and said conduit being a conductor of sea water from said bag andsaid first conduit being a conductor of oil into said cavity when it isdesired to store oil in said cavity.

References Cited in the file of this patent UNITED STATES PATENTS703,824 Quinn July 1, 1902 2,037,989 Macklanburg Apr. 21, 1936 2,387,598Mercier Oct. 23, 1945 2,869,328 Gibson Jan; 20, 1959 2,942,424 HobleJune 28, 1960 FOREIGN PATENTS 63,661 Norway June 30, 1941 1,113,631France Dec. 5, 1955

